[Hemoglobinopathies and arterial pathology]

Mutation of the hemoglobin molecule which characterises sickle cell anemia causes the falciformation under conditions of slow oxygen pressure, an increase in blood viscosity and premature destruction of the red blood cells. The vascular disorders, which are of variable nature, intensity and gravity, influence to a great extent the disabling character of the disease. Vaso occlusive crises are often associated with intercurrent infection. The retinopathy (well demonstrated by fluorescein angiography) is the most typical arteriolar disorder. In homozygotic patients, stenosis of the proximal portions of the large arteries leads to cerebrovascular complications, probably related to microcirculatory defects, responsible for variable clinical problems and some Moya-moya syndromes of childhood. From the therapeutic point of view, early treatment (transfusion and rehydration) allows regression without sequelae. Prevention is based on patient education to avoid triggering factors and a number of investigations, none of which has yet provided an absolute solution.